Friends and other related groups of people often want to be able to locate and track each other, as well as to possibly share information such as their current surroundings, sights, and feelings. For example, consider a large group of people together on a sightseeing tour or visiting a large amusement park. After arriving, they naturally break into subgroups (or squads), each with different interests and priorities, thus moving along different routes.
However, there is presently no reasonable way to locate, track and share data with one another in such squads, even though many people carry wireless communication devices such as Smartphones and the like. For example, while it is possible to call, leave a voice message, send a text message and so forth to another person, such existing solutions are not desirable or not as effective in certain circumstances. Wireless devices are subject to bandwidth limitations, require costly cellular data service, have battery power constraints, and have relatively small computational capacities. When combined with users' frequent location changes, there is heretofore no known way to perform cost-effective tracking and/or data sharing that overcomes the above-mentioned resource limitations, while maintaining data consistency for dynamic data.